@Article{cm,
  author = 	 {S. Chawathe and H. Garcia-Molina and and J. Widom},
  title = 	 {Flexible constraint management for autonomous
                 distributed databases}, 
  journal = 	 {Data Engineering Bulletin},
  year = 	 1994,
  volume =	 17,
  number =	 2,
  pages =	 {23--27}
}